The windshield and/or rear window of automotive vehicles often have an electrical device such as an antenna or defroster formed on or in the glass. In order to electrically connect the electrical device to associated equipment, for example, a radio, telephone, or defroster control, an electrical terminal is first soldered to the glass in electrical communication with the electrical device. An electrical cable extending from the associated equipment is then secured to the electrical terminal for providing electrical communication therebetween. A problem with some current electrical terminals is that the terminals can be easily separated from the glass by peeling if accidental pulling forces are exerted on the electrical cable. In addition, some electrical terminal designs are prone to cause cracking of the glass during soldering because of heat related stress concentrations formed on the glass by the footprint of the terminal.
The present invention provides an electrical terminal which is less readily separated from glass by accidental pulling forces than current terminal designs. In addition, the present invention electrical terminal has a design which causes little or no cracking of glass during soldering. The present invention is directed to an electrical terminal which includes a base pad for soldering to a surface. The base pad has a curved perimeter, and top and bottom surfaces. The electrical terminal also includes a securement portion having a deformable member for deforming around a conductor wire to capture and secure the conductor wire directly to the securement portion. The securement portion is configured relative to the base pad such that forces exerted by the conductor on the base pad are directed to a central region of the base pad.
In preferred embodiments, the base pad is formed of sheet metal and is generally circular in shape. The bottom surface of the base pad has a layer of solder thereon. In one embodiment, the securement portion includes a deformable strap located at the central region of the base pad formed by two opposed slits in the base pad. The slits allow the insertion of the conductor wire therethrough for capture between the top surface of the base pad and the strap.
In another embodiment, the securement portion includes an arm having proximal and distal ends extending from the central region of the base pad for directing forces exerted by the conductor wire to the central region. The proximal end extends from the central region and is defined by two opposed slots formed in the base pad extending from the perimeter of the base pad to the central region. The distal end has opposed crimping tabs for securing directly to the conductor wire. A portion of the arm is bent upwardly at an angle at about the perimeter of the base pad for absorbing forces exerted on the arm by the conductor wire. The distal end of the arm is bent to be parallel with the base pad.
The present invention also provides an electrical terminal assembly which enables easy soldering of multiple terminals with proper spacing therbetween. The terminal assembly includes at least two terminals, each having a base pad for soldering to a surface. Each base pad is secured to a conductor wire. A carrier strip is attached to the base pads by breakable regions.
The present invention further provides a method of soldering multiple electrical terminals to a surface, including providing an electrical terminal assembly having at least two terminals, each having a base pad for soldering to the surface. The base pads are secured to respective conductor wires and are attached to a carrier strip by breakable regions. The base pads are soldered to the surface with the carrier strip providing the proper spacing between the base pads. Once the base pads are soldered, the carrier strip is separated from the base pads by bending the carrier strip upwardly, thereby breaking the breakable regions.
In the present invention electrical terminal, by directing forces exerted by the conductor to the central region of the base pad, the strength of the solder joint between the base pad and the underlying surface, typically glass, is maximized. As a result, the terminal is not readily separated from the glass by accidental pulling forces. In addition, by having a generally circular base pad, the base pad of the present invention forms little or no heat related stress concentrations on the glass during soldering so that little or no cracking of the glass occurs. Consequently, the present invention provides a terminal that may be soldered to glass in a reliable manner and remain soldered thereto during normal use. Finally, the present invention electrical terminal assembly allows multiple electrical terminals to be quickly and easily soldered with the proper spacing therebetween, thereby allowing the manufacturing process to be conducted more quickly.